1. Field of the Invention
The present invention relates to pavement diamond grinders and in particular to large scale pavement diamond grinders.
2. Description of the Prior Art
Pavement diamond grinders are used for grinding concrete and asphalt surfaces. Grinding is done to remove irregularities in the road surface, to provide texture to the surface to prevent skidding, and also to groove the surface to facilitate water drainage. Grinding, texturing and grooving are used on pavement surfaces including highways, airport runways and bridge decks, at industrial plants, and at stock pens and barns.
The diamond tipped blades which are used to grind the concrete or asphalt surface are mounted on a rotating arbor. The arbor is mounted on an undercarriage of the grinder so that end portions of the arbor are supported by bearings. According to the prior art, end portions of the arbor are mechanically driven by a system of belts and pulleys. The power supplied from the mechanical drive limits the torque supplied to the arbor. The width of the arbor cutting surface is then limited as greater power is required as more blades are added for a longer cutting surface. Because of power considerations, grinders have heretofore been limited to arbors having a three foot cutting width.
The width of the cutting path affects the time required to perform the grinding or grooving work. When grinding and grooving are performed, adjoining cuts must be precisely aligned to ensure proper cutting depth and an even pavement surface. The alignment process for each pass and added cutting passes due to narrower cutting heads greatly increase the time required for grinding.
The grinding and grooving processes create a substantial amount of debris in the form of concrete dust and particles. In addition, water is sprayed for dust control, cooling and lubricating. The resulting slurry must be removed from the pavement surface. Suction is used to continually remove the debris and water from the pavement so that the area where grinding occurs is kept clear.
The debris removed from grinding is very hard and abrasive, leading to severe wear problems on the debris removal equipment. The prior art removal systems use a cyclonic separator to separate the debris and water from the air flow. In a cyclonic separator, the debris is swirled around a circular upper portion of the separator and passed downward as it swirls along conical walls of the lower portion of the separator to an outlet at the bottom of the separator where it is pumped for disposal. The swirling action of the debris is especially abrasive, so that as the debris is swirled around the upper portion of the separator, the debris wears against the walls. The separator walls must then be replaced on a regular basis, adding a substantial expense and forcing equipment downtime.
In addition to having wear problems, the cyclonic separator chamber of prior art grinders accumulates debris when a clog in the disposal system occurs. The debris may back up further into the system and may damage the vacuum pump. The separator should provide a stop point to prevent debris from being drawn into the vacuum pump. When debris backs up, the separator must be cleaned before grinding may resume, causing substantial down time. It is therefore important that the chamber be easily cleaned should there be a backup in the debris removal system.
It can be seen then, that an improved pavement grinder is needed that provides a wider, directly driven cutting head. It can be appreciated that the debris removal system surrounding the arbor must be able to remove the debris created by grinding to keep the grinding area clear. It can also be seen that a separation tank is needed that limits the amount of wear and reduces the maintenance costs incurred due to wear and overcomes vacuum pump damage due to clogs in the system. The present invention solves these and other problems associated with pavement grinding.